Abstract:Satellite based technology precipitation monitoring is to build the relationship between the temperature of the cloud head and the precipitation of a pixel and use the satellite cloud information to interpolate rainfall between the surface rain gauges. The calculation of actual evapotranspiration includes following steps: calibration, air temperature mapping, atmospheric correction, calculation of net radiation, calculation of the sensible heat flux, determination of the actual evapotranspiration. Snowfall, snow thaw, soil freeze and soil melt are dealt with based on energy balance and the temperature. The runoff over the slope is simulated by two dimension diffusing process and flow routing in river channel by Muskingum-Cunge method with lateral inflow.